Power converting apparatus with drive signal path impedance increasing circuitry

ABSTRACT

A power converting apparatus is obtained in which an integrated circuit for driving a power switching element is operated under stable conditions. A core 100 functioning as a common mode transformer made of a material such as ferrite is connected to a wiring line connected between a switch 7, a switch 8, and an IC 13 for opening/closing these switches 7 and 8 in a complementary manner, so that an impedance of a current path to the switch 7 and the IC 13 is increased.

TECHNICAL FIELD

The present invention is related to a power switching element and alsoto a power converting apparatus including a control IC for controllingthis power switching element.

TECHNICAL BACKGROUND

FIG. 24 represents a connection between a power switching element forconstructing a conventional power converting apparatus, and a control ICfor driving/controlling this power switching element. In this drawing,reference numerals 1 to 4 show DC power supplies, reference numeral 5indicates a resistor, reference numeral 6 represents a reactor,reference numerals 7 and 8 show switches, reference numerals 9 and 10denote diodes, reference numeral 11 and 12 show resistors, and referencenumeral 13 denotes an IC for driving the above-described switches 7 and8.

The above-explained power supplies 1 and 2 are such power supplies forsupplying energy to a load constituted by the above-described resistor 5and the above-explained reactor 6. The power supply 3 is such a powersupply for supplying electric power between a VB-terminal and aVS-terminal, corresponding to power supply terminals of the IC 13 fordriving the switch 7. The DC power supply 4 is such a power supply forsupplying electric power between a VCC-terminal and a COM-terminal ofthe IC 13 for driving the switch 8. The above-explained resistors 11 and12 are drive resistors for driving the switches 7 and 8.

A signal HIN and a signal LIN, corresponding to the respective switches7 and 8, are inputted to the IC 13. When the above signal HIN is "high",an output HO of the IC 13 becomes "high". When the above signal HIN is"low", an output LO of the IC 13 becomes "low". Similarly, when theabove signal LIN is "high", an output LO of the IC 13 becomes "high".When the above signal LIN is "low", an output LO of the IC 13 becomes"low".

Also, in FIG. 24, it is now that a voltage applied to a load constructedof the resistor 5 and the resistor 6 is "VL"; a current flowing throughthe load is "IL"; a voltage applied between the VS terminal and the COMterminal in the IC 13 is "Vrev"; a current flowing through a wiring lineused to connect an emitter of the switch 8 and the COM terminal of theIC 13 is "Irev"; and voltages of the DC power supply 1 and of the DCpower supply 2 are "E". It should be noted that plus polarities of therespective voltages and the respective currents are directed, as viewedin FIG. 24.

Next, a description will now be made of a power supplying method to theload with reference to FIG. 24 and FIG. 25. At this time, it is assumedthat the above-described load current IL is directed to a plusdirection. In FIG. 25, (a) shows an operation of the switch 7; (b)indicates an operation of the switch 8; (c) represents a waveform of theload voltage VL; (d) shows a waveform of the load current IL; (e)represents a waveform of a current flowing through the switch 7; and (f)indicates a waveform of a current flowing through the diode 10.

In the drawings, when the switch 7 is turned OFF and the switch 8 isturned ON, the load voltage becomes "-E", and then the magnitude of theload current IL is decreased. In this case, the above-described loadcurrent IL actually does not flow through the switch 8, but flowsthrough the diode 10. Next, when the switch 7 is turned ON and theswitch 8 is turned OFF, the load voltage becomes +E. The magnitude ofthe load current IL is increased. At this time, the load current ILflows through the switch 7. In other words, when the ON/OFF controls ofthe switches 7 and 8 are carried out, the load voltage VL can becontrolled, and therefore the above-explained load current IL can becontrolled.

Also, FIG. 26 shows an internal circuit of the above-described IC 13. Inthis drawing, reference number 21 shows a rising edge detecting circuitfor detecting a rising edge of the above-described signal HIN, referencenumeral 22 indicates a falling edge detecting circuit for detecting afalling edge of the signal HIN, and reference numeral 23 represents anMOSFET which is turned ON when an output of the rising edge detectingcircuit 21 is high, and which is turned OFF when the output of thefalling edge detecting circuit 21 is low. Reference numeral 24represents a MOSFET which is turned ON when an output of the rising edgedetecting circuit 22 is high, and which is turned OFF when the output ofthe falling edge detecting circuit 21 is low. Reference numerals 25 and26 are parasitic diodes of the above-described MOSFET 23 and MOSFET 24,reference numerals 27 and 28 show resistors, reference numerals 29 and30 indicate zener diodes, reference numeral 31 denotes a flip-flop, andreference numerals 32 and 33 are buffer amplifiers for outputting theabove-described signals HO and LO. The zener diodes 29 and 30 areconnected so as to protect overvoltage on the input side of theflip-flop 31.

Next, operations of the above-explained IC 13 will now be explained withreference to FIG. 27. In FIG. 27, (a) shows a waveform of theabove-explained signal HIN; (b) indicates a waveform of theabove-described signal LIN; (c) represents an output waveform of therising edge detecting circuit 21; (d) shows an output waveform of thefalling edge detecting circuit 22; (e) indicates an S-input waveform ofthe flip-flop 31; (f) represents an R-input waveform of the flip-flop31; (g) shows a waveform of the output Q of the flip-flop 31; (h)denotes a waveform of the signal HO; and (i) denotes a waveform of thesignal LO. The signal LIN is directly outputted via the buffer amplifier33 as the above-explained signal LO.

First, a description will now be made of a time instant "t1" when theabove-explained signal HIN is transferred from "low" to "high". At thistime, the output waveform of the rising edge detecting circuit 21becomes high during a predetermined time period, so that the MOSFET 23is turned ON.

As a result, since the current flows through the resistor 27, a voltagedrop occurs at the resistor 27, and the S-input of the flip-flop 31becomes "low". Then, the flip-flop 31 is set, so that the signal Qbecomes "high".

Next, a description will now be made of a time instant "t2" when theabove-explained signal HIN is transferred from "high" to "low". At thistime, the output waveform of the rising edge detecting circuit 22becomes high during a predetermined time period, so that the MOSFET 24is turned ON.

As a result, since the current flows through the resistor 28, a voltagedrop occurs at the resistor 28, and the R-input of the flip-flop 31becomes "low". Then, the flip-flop 31 is reset, so that the signal Qbecomes "low".

Since the signal Q is directly outputted via the buffer amplifier 32 asthe signal HO, both the above-described signal HIN and signal HO aremade substantially coincident with each other.

The above-explained conventional power converting apparatus has such amerit that since the circuit becomes non-insulating conditions from thesignal HIN up to the signal HO and from the signal LIN up to the signalLO, the signal transfer delay is small, as compared with the signaltransfer via the electric insulation by the photocoupler and the like,and therefore the signal can be more accurately transferred.

Next, with reference to FIG. 28 to FIG. 30, a description will now bemade of operations when the above-described load current IL iscommutated from the switch 7 to the diode 10. In FIG. 28, it is nowassumed that a current flowing through the switch 7 is "IL1". In FIG.29, reference numerals 40 to 42 indicate wiring line inductance. It isalso assumed that a current flowing through the diode 10 is "IL2". Also,in FIG. 30, (a) shows a waveform of the above-described current IL1; (b)represents a waveform of the above-explained current IL2; and (c)represents a waveform of the above-explained voltage Vrev. In a timeperiod shown in FIG. 30, the above-explained current IL is substantiallyconstant. As indicated in FIG. 28, firstly, the switch 7 is turned ONand the switch 8 is turned OFF. Thus, it is assumed that theabove-described load current IL flows via the switch 7.

Next, at the time instant t1, if an OFF-instruction is given to theswitch 7 and an ON-instruction is given to the switch 8, then thecurrent IL1 is gradually reduced, as indicated in FIG. 30. At a timeinstant t2, this current IL1 becomes zero. Also, the current IL2 isgradually increased, and then becomes IL at the time instant t2. At thistime, IL=IL1+IL2 can be established.

During the above-described commutation operation, a voltage is producedin direct proportional to an inclination of a current directed, as viewin the drawing, in the above-described wiring inductance 40 to 42. Atthe same time, a drop voltage along a forward direction is produced inthe diode 10. A summation of these voltages appears as theabove-described voltage Vrev. A waveform of this voltage Vref isschematically shown in FIG. 30(c).

Also, in FIG. 31, to achieve a withstanding voltage in the IC 13, theabove-described terminal VB is separated from the above-explainedterminal COM by a PN junction. In other words, a parasitic diode 50 ispresent. As a consequence, when the voltage Vrev becomes negative andthe magnitude of this voltage exceeds the voltage V3 of the DC powersupply 3, the above-explained parasitic diode 50 is turned ON. A currentflows through the COM terminal--the parasitic diode 50--the VBterminal--the DC power supply 3, and the wiring line impedance of thepath. When the magnitude of the voltage Vrev is lower than the voltageV3 of the DC power supply 3, a reverse current flows through theparasitic diode 50, and thereafter this parasitic diode 50 is turnedOFF. At this stage, waveforms are schematically indicated in FIG. 32.FIG. 32(a) shows the voltage Vrev, and FIG. 32(b) represents the currentIrev. As a consequence, a current as indicated in FIG. 32(b) will flowinside the IC 13.

Also, the buffer amplifier 32 is arranged as shown in FIG. 33. In otherwords, reference numeral 52 shows a p type MOSFET, and reference numeral53 indicates an n type MOSFET. Two MOSFETs 52 and 53 constitute aso-called "CMOS structure".

When the above-explained CMOS structure is rewritten into asemiconductor structural diagram, such a semiconductor structuraldiagram is made as shown in FIG. 34. Assuming now that an n-typesubstrate is used as a substrate, a p well is employed while an n typeMOSFET is fabricated. In this structure, a transistor 62 and anothertransistor 63 are parasitically present. Also, a resistor 60 and anotherresistor 61 are parasitically present on the substrate.

It is now assumed that a current may flow from the VB terminal into then-type substrate. At this time, at the resistor 60, a voltage dropappears along a direction of "+" and "-", as indicated in this drawing,so that the above-explained transistor 62 is turned ON. As a result, acurrent flows from the VB-terminal via the resistor 61 to theVS-terminal, so that a voltage drop appears at the resistor 61 along adirection of "+" and "-", as shown in this drawing, and then thetransistor 63 is turned ON. As a consequence, since both the VB-terminaland the VS-terminal shortcircuit the DC power supply 3 via the twoturned-ON transistors, not only the erroneous operation of the CMOSstructure occurs, but also this CMOS structure is thermally destroyed bythe overcurrent. That is, a latch-up phenomenon happens to occur.

When the above-described current Irev is sufficiently large, this maycause the above-mentioned latch-up phenomenon. There is a problem thatthe IC 13 is erroneously operated, or is electrically destroyed.

Also, when the magnitude of the IC 13 is higher than the voltage V3 ofthe DC power supply 3, the above-described current Irev may flow throughthe COM-terminal--diode 25--the zener diode 29--the VB-terminal--the DCpower supply 3, and the wiring line impedance of the signal path.

Referring now to FIG. 35, operations when the above current may flowwill be explained. In FIG. 35, (a) shows a waveform of the current Irev;(b) indicates a waveform of a current flowing through the diode 25; (c)represents a waveform of a current flowing through the diode 29; and (d)shows a waveform of an S-input of the flip-flop 31.

When the voltage Vrev is lower than the voltage VB of the DC powersupply 3 at the time instant t1, since the diode 25 and the zener diode29 are turned OFF, the circuit operation is entered into the reverserecovery operation, so that minus currents will flow through therespective diodes, as represented in this drawing. At this time, as tothe electric charge amount for the reverse recovery, if the changeamount of the diode 25 is larger than that of the zener diode 29, asshown in this drawing, the zener diode 29 accomplishes the reverserecovery operation at the time instant t2, and then is turned OFF. Sincethe diode 25 is still under reverse recovery operation, the minuscurrent continuously flows. Thereafter, at a time instant t3, thereverse recovery operation of the diode 25 is completed and this diode25 is turned OFF.

At this time, the minus current flowing through the diode 25 will flowthrough the resistor 27. As a consequence, the S-input waveform of theflip-flop 31 becomes low, as shown in the drawing. Therefore, there is aproblem that the output signal of the flip-flop 31 is transferred from a"low" state to a "high" state, and this flip-flop 31 is erroneouslyignited.

In other words, as shown in FIG. 36, the above-described current Irevmay cause a problem, which flows when the high voltage Vrev is producedalong the minus direction.

To solve this problem, as indicated in FIG. 37, in the conventionalpower converting apparatus, the resistor 70 is connected to the resistor71, and it is so set: the value of resistor 11=the value of resistor70+the value of resistor 71 in order to increase the impedance of thesignal path through which the current Irev flows. As a result, since theabove-described current Irev can be suppressed, it is possible tosuppress the erroneous operation and the electric destruction of the IC13.

Also, in another conventional power converting apparatus, as indicatedin FIG. 38, since the diode 72 is connected between the COM terminal andthe VS terminal of the IC 13, the current Irev is bypassed by the diode72, so that the current flowing through the IC 13 can be suppressed.Thus, it is possible to suppress the erroneous operation and theelectric destruction of the IC 13.

However, generally speaking, in FIG. 37, in such a case that the switch7 is selected as a switch element having a large capacity, since thedrive resistance value for driving the switch 7 is set to a smallresistance value, the resistance value of the resistor 71 must be set toa small value. Thus, there is a problem that such an impedance capableof suppressing the above-described current Irev cannot be obtained.

Also, in FIG. 38, since the current Irev is shunted based upon a ratioof the impedance of the signal path passing through the diode 72 to theimpedance of the signal path passing through the IC 13, there are somecases that the current flowing through the IC 13 cannot be completelysuppressed, depending upon the characteristic and the connecting way ofthe diode 72. Also, since the anode and the cathode of theabove-described diode 72 are connected to the emitter of the switch 8and the emitter of the switch 7, when the voltages of theabove-described DC power supply 1 and DC power supply 2 are high, thewithstanding voltage of the diode 72 must be selected to be a highwithstanding voltage in connection with these high voltages. As aconsequence, there is another problem that the reliability isdeteriorated, and the cost is increased.

DISCLOSURE OF THE INVENTION

A power converting apparatus, according to the present invention, iscomprised of: an electric valve group containing a first electric valveand a second electric valve, which have first terminals, secondterminals, and third terminals, and in which the first terminals and thethird terminals are opened/closed by supplying an electric signalbetween the second terminals and the third terminals, and also the firstelectric valve is series-connected to the second electric valve; a powersupply group containing a first power supply and a second power supplyseries-connected to the first power supply, the power supply group beingconnected in parallel to the electric valve group; a load connectedbetween a junction point defined by the first electric valve and thesecond electric valve, and another junction point defined by the firstpower supply and the second power supply; control means connected to thesecond terminals in the first and second electric valves and also to thethird terminals in the first and second electric valves, foropening/closing the first and second electric valves in a complementarymanner; a third power supply, one end of which is connected to thecontrol means, and the other end of which is connected to the thirdterminal in the first electric valve; a fourth power supply, one end ofwhich is connected to the control means, and the other end of which isconnected to the third terminal in the second valve; and impedanceincreasing means for increasing an impedance of a signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the electricvalve.

Also, the impedance increasing means is a transformer.

Furthermore, the transformer is hollow; and a line used to connect thesecond terminal in the second electric valve with the control means andanother line used to connect the third terminal in the second electricvalve with the control means are provided in such a manner that both thelines penetrate the hollow of the transformer.

Moreover, the transformer is hollow; and a line used to connect thesecond terminal in the first electric valve with the control means andanother line used to connect the third terminal in the first electricvalve with the control means are provided in such a manner that both thelines penetrate the hollow of the transformer.

Also, the line used to connect the second terminal in the secondelectric valve with the control means and the line used to connect thethird terminal in the second electric valve with the control means areprovided in such a manner that both the lines penetrate the hollow ofthe transformer plural times.

Further, the line used to connect the second terminal in the firstelectric valve with the control means and the line used to connect thethird terminal in the first electric valve with the control means areprovided in such a manner that both the lines penetrate the hollow ofthe transformer plural times.

Moreover, the transformer is hollow; and a line used to connect thesecond terminal in the first electric valve with the control means,another line used to connect the third terminal in the first electricvalve with the control means, another line used to connect the secondterminal in the second electric valve with the control means, andanother line used to connect the third terminal in the second electricvalve with the control means are provided in such a manner that thelines penetrate the hollow of the transformer.

Also, the impedance increasing means is a resistor.

Furthermore, the third power supply is connected via the resistor to thecontrol means.

Moreover, the power converting apparatus is comprised of a diodeconnected in parallel to the resistor.

Also, the impedance increasing means includes: a diode series-connectedbetween the control means and the third power supply; a capacitorconnected in parallel to the diode and the third power supply; and aresistor series-connected to the capacitor and also connected inparallel to both the diode and the third power supply.

A power converting apparatus, according to the present invention, iscomprised of: a first electric valve provided so as to supply power froma first power supply to a load; a second electric valve provided so asto supply power from a second power supply to the load; control meansfor controlling a switching operation of conducting the first electricvalve and the second electric valve in a complementary manner bysupplying a switching control signal to a control electrode of the firstelectric valve and also to a control electrode of the second electricvalve; a third power supply connected between one of main electrodes ofthe first electric valve and the control means; a fourth power supplyconnected between one of main electrodes of the second electric valveand the control means; and impedance increasing means provided in aseries circuit constituted by a main electrode of the second electricvalve, the control means, the third power supply, and a main electrodeof the first electric valve, for increasing an impedance of the seriescircuit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 1.

FIG. 2 is a diagram for showing such a case that a connection line iswound on a core by two turns.

FIG. 3 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 2.

FIG. 4 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 3.

FIG. 5 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 4.

FIG. 6 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 5.

FIG. 7 is a circuit diagram for indicating a power converting apparatusaccording to an embodiment 6.

FIG. 8 is a diagram for showing a method for connecting a 3-phase powerconverting circuit with three ICs.

FIG. 9 is a diagram for representing a current path which may causeerroneous operation and electric destruction of the three ICs when the3-phase power converting circuit is connected to the three ICs.

FIG. 10 is a circuit diagram for representing a power convertingapparatus according to an embodiment 7.

FIG. 11 is a circuit diagram for representing a power convertingapparatus according to an embodiment 8.

FIG. 12 is a circuit diagram for representing a power convertingapparatus according to an embodiment 9.

FIG. 13 is a circuit diagram for representing a power convertingapparatus according to an embodiment 10.

FIG. 14 is a circuit diagram for representing a power convertingapparatus according to an embodiment 11.

FIG. 15 is a circuit diagram for representing a power convertingapparatus according to an embodiment 12.

FIG. 16 is a circuit diagram for indicating a method for connecting a3-phase power converting circuit to a single IC.

FIG. 17 is a circuit diagram for representing a current path which maycause erroneous operation and electric destruction of the IC when the3-phase power converting circuit is connected to a single IC.

FIG. 18 is a circuit diagram for representing a power convertingapparatus according to an embodiment 13.

FIG. 19 is a circuit diagram for representing a power convertingapparatus according to an embodiment 14.

FIG. 20 is a circuit diagram for representing a power convertingapparatus according to an embodiment 15.

FIG. 21 is a circuit diagram for representing a power convertingapparatus according to an embodiment 16.

FIG. 22 is a circuit diagram for representing a power convertingapparatus according to an embodiment 17.

FIG. 23 is a circuit diagram for representing a power convertingapparatus according to an embodiment 18.

FIG. 24 is a circuit diagram for indicating the conventional powerconverting apparatus.

FIG. 25 is a diagram for showing the switch operation of theconventional power converting apparatus, and the waveforms of thevoltage and the current.

FIG. 26 is a diagram for indicating an internal circuit of an IC.

FIG. 27 is a diagram for explaining operation of the IC.

FIG. 28 is a diagram for showing the operation of the conventional powerconverting apparatus.

FIG. 29 is a diagram for showing the operation of the conventional powerconverting apparatus.

FIG. 30 is a diagram for representing the voltages and the currents inthe conventional power converting apparatus.

FIG. 31 is a diagram for showing the internal circuit of the IC.

FIG. 32 is a diagram for denoting the mechanism as to how the currentflows through the IC.

FIG. 33 is a diagram for indicating the buffer amplifier structure ofthe IC.

FIG. 34 is a diagram for indicating the buffer amplifier structure ofthe IC.

FIG. 35 is a diagram for representing the mechanism as to how the IC iserroneously operated.

FIG. 36 is a diagram for indicating the current path when the IC iserroneously operated, or is electrically destroyed.

FIG. 37 is a diagram for representing the solving example executed inthe conventional power converting apparatus.

FIG. 38 is a diagram for representing the solving example executed inthe conventional power converting apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION

Now, a description will be made of embodiments according to the presentinvention.

EMBODIMENT 1

FIG. 1 indicates a power converting apparatus according to an embodimentof the present invention. In this drawing, reference numerals 1 to 13indicate the same circuit elements of the above-explained conventionalpower converting apparatus, and explanations thereof are omitted.Reference numeral 100 indicates a core (common mode transformer) made ofa material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev penetrates the core 100 by 1 time,the core 100 many function as an inductance component with respect tothe current Irev. In other words, the impedance of the signal path ofthe above-explained Irev is increased.

When the impedance of the signal path of the current Irev is increased,this current Irev can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current flowing through a current path used to drive the switch 8,namely a current flowing from the LO-terminal of the IC 13 via theresistor 12, the gate of the switch 8, and the emitter of the switch 8to the COM terminal of the IC 13 penetrates the core 100 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 100 are canceled with each other, so that the core 100 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 8 caused by connecting the above-explainedcore 100 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Originally, since the above-described current Irev flows through the IC13, and the current value is low, a low-cost core can be used as thecore 100.

Also, as indicated in FIG. 2, when the power converting apparatus isarranged in such a manner that the above-described current Irevpenetrates the core 100 two times, since an impedance component withrespect to the signal path through which the above-explained currentIrev flows is increased, the current Irev can be furthermore suppressed,and the erroneous operation of the IC 13 and the electric destructionthereof can be prevented.

It should be noted that in FIG. 2, the current Irev penetrates the core100 two times. In general, it may be so arranged that theabove-described current Irev may pass through the core 100 plural times.

In FIG. 1 and FIG. 2, the power converting apparatuses are arranged byemploying only one core. Alternatively, it is apparently possible toarrange the power converting apparatus by employing a plurality ofcores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise.

Also, since the magnetic flux produced in the common mode transformer issmall, a low-cost common mode transformer may be used as theabove-described common mode transformer.

Also, it is possible to prevent the erroneous operation of the IC andthe electric destruction thereof without giving an adverse influence tothe switching speed of the electric valve.

It should also be noted that this embodiment has described such acircuit that the power supply 1 and the power supply 2 are separatelyprovided. Alternatively, this circuit may be arranged by employing acommon power supply capable of commonly using these power supplies. Evenin this case, the common power supply functionally includes the powersupply 1 and the power supply 2. This point is similarly applied to thesubsequent embodiments.

It should be understood in this specification that the emitters and thecollectors of the switches 7 and 8 will also be referred to as "mainelectrodes", and the bases of these switches 7 and 8 will also bereferred to as "control electrodes".

In this embodiment, as the load, the resistor 5 is series-connected tothe reactor 6. Alternatively, any one of the resistor 5 and the reactor6 may be employed.

EMBODIMENT 2

FIG. 3 indicates a power converting apparatus according to a secondembodiment of the present invention. In this drawing, reference numerals1 to 13 indicate the same circuit elements of the above-explainedconventional power converting apparatus, and explanations thereof areomitted. Reference numeral 101 indicates a core (common modetransformer) made of a material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev penetrates the core 101 by 1 time,the core 101 may function as an inductance component with respect to thecurrent Irev. In other words, the impedance of the signal path of theabove-explained Irev is increased.

When the impedance of the signal path of the current Irev is increased,this current Irev can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current flowing through a current path used to drive the switch 7,namely a current flowing from the HO-terminal of the IC 13 via theresistor 11, the gate of the switch 7, and the emitter of the switch 7to the VS terminal of the IC 13 penetrates the core 101 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 101 are canceled with each other, so that the core 101 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 7 caused by connecting the above-explainedcore 101 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Originally, since the above-described current Irev flows through the IC13, and the current value is low, a low-cost core can be used as thecore 101.

Also, the power converting apparatus is arranged in such a manner thatthe above-described current Irev may penetrate the core 101 by pluraltimes.

Alternatively, it is apparently possible to arrange the power convertingapparatus by employing a plurality of cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise. Also, similarly, the drive signal path(namely, terminal LO--resistor 12--switch 8--terminal COM) via theresistor 12 may be connected under twist line condition for suppressinginduction noise.

EMBODIMENT 3

FIG. 4 indicates a power converting apparatus according to a thirdembodiment of the present invention. In this drawing, reference numerals1 to 13 indicate the same circuit elements of the above-explainedconventional power converting apparatus, and explanations thereof areomitted. Reference numerals 102 and 104 indicate cores (common modetransformers) made of a material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev penetrates the core 103 by 1 timeand the core 104 by 1 time, the cores 103 and 104 may function asinductance components with respect to the current Irev. In other words,the impedance of the signal path of the above-explained Irev isincreased.

When the impedance of the signal path of the current Irev is increased,this current Irev can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current flowing through a current path used to drive the switch 8,namely a current flowing from the LO-terminal of the IC 13 via theresistor 12, the gate of the switch 8, and the emitter of the switch 8to the COM terminal of the IC 13 penetrates the core 104 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 104 are canceled with each other, so that the core 104 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 8 caused by connecting the above-explainedcore 104 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Also, a current flowing through a current path used to drive the switch7, namely a current flowing from the HO-terminal of the IC 13 via theresistor 11, the gate of the switch 7, and the emitter of the switch 7to the VS terminal of the IC 13 penetrates the core 103 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 103 are canceled with each other, so that the core 103 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 7 caused by connecting the above-explainedcore 103 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Originally, since the above-described current Irev flows through the IC13, and the current value is low, a low-cost core can be used as thecores 103 and 104.

It should be noted that it may be so arranged that the above-describedcurrent Irev may pass through the cores 103 and 104 plural times.

Alternatively, it is apparently possible to arrange the power convertingapparatus by employing a plurality of the above-described cores 103 and104.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise. Also, similarly, the drive signal path(namely, terminal LO--resistor 12--switch 8--terminal COM) via theresistor 12 may be connected under twist line condition for suppressinginduction noise.

EMBODIMENT 4

FIG. 5 indicates a power converting apparatus according to a fourthembodiment of the present invention. In this drawing, reference numerals1 to 13 indicate the same circuit elements of the above-explainedconventional power converting apparatus, and explanations thereof areomitted. Reference numeral 105 indicates a core (common modetransformer) made of a material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev penetrates the core 105 by 2 times,the core 105 may function as an inductance component with respect to thecurrent Irev. In other words, the impedance of the signal path of theabove-explained Irev is increased.

When the impedance of the signal path of the current Irev is increased,this current Irev can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current flowing through a current path used to drive the switch 8,namely a current flowing from the LO-terminal of the IC 13 via theresistor 12, the gate of the switch 8, and the emitter of the switch 8to the COM terminal of the IC 13 penetrates the core 105 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 105 are canceled with each other, so that the core 105 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 8 caused by connecting the above-explainedcore 105 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Also, a current flowing through a current path used to drive the switch7, namely a current flowing from the HO-terminal of the IC 13 via theresistor 11, the gate of the switch 7, and the emitter of the switch 7to the VS terminal of the IC 13 penetrates the core 105 by 1 time alongdifferent directions to each other. The magnetic fluxes produced withinthe core 105 are canceled with each other, so that the core 105 does notfunction as an inductance component. In other words, the delay in thedrive speed of the switch 7 caused by connecting the above-explainedcore 100 is not produced, but also the erroneous operation of the IC 13and also the electric destruction thereof can be prevented.

Originally, since the above-described current Irev flows through the IC13, and the current value is low, a low-cost core can be used as thecore 105.

It should be noted that it may be so arranged that the above-describedcurrent Irev may pass through the core 105 more plural times.

Alternatively, it is apparently possible to arrange the power convertingapparatus by employing a plurality of cores 105.

Also, under such a condition that only one core is used due to low costand also, as represented in FIG. 2, the same drive wiring line cannotpenetrate such a single core by more than 2 times because of thearrangement of the power converting apparatus, only such an impedance ofa single core is merely obtained with respect to the current Irev. Tothe contrary, according to this embodiment, since the impedance for twosets of cores can be obtained, the current Irev can be furthermoresuppressed.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise. Also, similarly, the drive signal path(namely, terminal LO--resistor 12--switch 8--terminal COM) via theresistor 12 may be connected under twist line condition for suppressinginduction noise.

EMBODIMENT 5

FIG. 6 indicates a power converting apparatus according to a fifthembodiment of the present invention. In this drawing, reference numerals1 to 13 indicate the same circuit elements of the above-explainedconventional power converting apparatus, and explanations thereof areomitted. Reference numeral 110 indicates a resistor, and referencenumeral 111 shows a diode.

In the power converting apparatus with the above-described circuitarrangement, when the current Irev flows along a direction as shown inthe drawing, since the resistor 110 is present, this current Irev can besuppressed. As a result, it is possible to prevent the IC 13 from theerroneous operation and the electric destruction.

Also, in the case that the resistor 110 is provided in theabove-described manner, since it becomes high impedance due to theresistor 100, the impedance of this signal path must be lowered so as tosupply a drive power supply from the power supply 3 via the diode 111 toVB. To this end, the diode 111 is provided as shown in this drawing.

Also, since an impedance component is not newly added to a current pathused to drive the switch 7 under ON state, namely a signal path definedby the power supply 3--the diode 111--the HO terminal of the IC 13--theresistor 11--the gate of the switch 7--the emitter of the switch 7,there is no delay in the drive speed of the switch 7. It is, of course,no problem in such a case that the switch 7 is driven to the OFF state.

Also, since the above-described diode 111 is connected via the powersupply 3 to the VB-terminal of the IC 13 and the VS-terminal thereof,such a diode having a low rating voltage may be used, so that a low-costdiode may be employed as the diode 111.

As explained in the above-explained embodiment, when the ferrite core isemployed, the mechanism capacity (mechanism volume) is increased and thecost is increased. However, since both the resistor 110 and the diode111 are used, there is such an advantage that the space saving matterand the low cost aspect can be realized.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise. Also, similarly, the drive signal path(namely, terminal LO--resistor 12--switch 8--terminal COM) via theresistor 12 may be connected under twist line condition for suppressinginduction noise.

EMBODIMENT 6

In the case that the above-described DC power supply 3 is, for instance,such a DC power supply containing high frequency noise and highfrequency ripples such as a switching power supply, there are somepossibilities that a decoupling capacitor having a small capacitance anda better high frequency characteristic is connected between theVB-terminal and the VS-terminal, corresponding to the power supplyvoltage terminals of the IC 13 in order not apply the noise and theripple component. In this case, the current Irev will flow through theabove-described decoupling capacitor, so that the IC 13 is erroneouslyoperated, and is electrically destroyed.

FIG. 7 indicates a power converting apparatus according to a sixthembodiment of the present invention. In this drawing, reference numerals1 to 13 indicate the same circuit elements of the above-explainedconventional power converting apparatus, and explanations thereof areomitted. Reference numeral 112 indicates a diode, reference numeral 113shows a capacitor functioning as a decoupling capacitor, and referencenumeral 114 is a resistor.

The above-described current Irev is blocked by the diode 112, and thereis no path through which the current passes via the DC power supply 3.As a consequence, the current Irev will flow via the capacitor 113.However, since the resistor 114 is present, the current Irev issuppressed, so that the erroneous operation of the IC 13 and theelectric destruction thereof can be avoided. Also, if the resistancevalue of the resistor 114 may be set to a small value, then theimpedance of the high frequency component with respect to the DC powersupply 3 is not so increased. As a consequence, the high frequency noiseand the high frequency ripple in the DC power supply 3 can be absorbedin the path of the capacitor 113 and the resistor 114.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO--resistor 11--switch 7--terminal VS)via the resistor 11 is connected under twist line condition forsuppressing induction noise. Also, similarly, the drive signal path(namely, terminal LO--resistor 12--switch 8--terminal COM) via theresistor 12 may be connected under twist line condition for suppressinginduction noise.

In the above-described embodiment, since the impedance is increased byemploying the ferrite core, the apparatus capacity (appliance volume)and the apparatus cost are increased. However, in this embodiment, sincethe impedance is increased by employing the capacitor 113 and theresistor 114, the space saving and the cost saving can be realized.

EMBODIMENT 7

FIG. 8 represents such a case that a 3-phase power converting circuit isdriven by the above-described IC 13. In this drawing, reference numerals3, 4, and 13 indicate the same circuit elements of the above-describedconventional power converting apparatus, and explanations thereof areomitted. Reference numerals 206 to 208 show loads; reference numerals209 to 214 indicate switches; and reference numerals 215 to 220represent diodes. A 3-phase power converting circuit is arranged by theabove-described switches 209 to 214, and the above-explained diode 215to 220. Reference numerals 221 to 226 show resistors; reference numerals230 to 233 indicate DC power supplies; reference numeral 240 indicatesan IC for driving the above-explained switches 211 and 212; andreference numeral 241 denotes an IC for driving the above-mentionedswitches 213 and 214.

The above-explained DC power supply 201 is such a power supply forsupplying energy to the above-described loads 206 to 208. Theabove-described DC power supply 230 is a power supply for supplyingelectric power between a VB-terminal and a VS-terminal, equal to powersupply voltage supplying terminals of the IC 240 for driving the switch211, and the above-described DC power supply 231 is a power supply forsupplying electric power between a VCC-terminal and a COM-terminal,equal to power supply voltage supplying terminals of the IC 240 fordriving the switch 212. The above-described DC power supply 232 is apower supply for supplying electric power between a VB-terminal and aVS-terminal, equal to power supply voltage supplying terminals of the IC241 for driving the switch 213, and the above-described DC power supply233 is a power supply for supplying electric power between aVCC-terminal and a COM-terminal, equal to power supply voltage supplyingterminals of the IC 241 for driving the switch 214. The above-explainedresistor 221 is a drive resistor for driving the above-mentioned switch209, the above-mentioned resistor 222 is a drive resistor for drivingthe above-explained switch 211, and the above-described resistor 223 isa drive resistor for driving the above-described resistor 213. Also, theabove-explained resistor 224 is a drive resistor for driving theabove-mentioned switch 210, the above-mentioned resistor 225 is a driveresistor for driving the above-explained switch 212, and theabove-described resistor 226 is a drive resistor for driving theabove-described resistor 214.

In the above-described IC 13, a signal UP corresponding to the switch209 is entered into an HIN-terminal, and another signal UN correspondingto the switch 210 is entered into an LIN terminal. Also, in theabove-explained IC 240, a signal VP corresponding to the switch 211 isentered into an HIN terminal, and another signal VN corresponding to theswitch 212 is entered into an LIN terminal. Further, in theabove-described IC 24, a signal WP corresponding to the switch 213 isentered into an HIN-terminal, and another signal WN corresponding to theswitch 214 is entered into an LIN terminal. When the signal UP is high,the output HO of the IC 13 becomes high, whereas the signal LIP is low,the output HO of this IC 13 becomes low. Similar to the above case, whenthe signal UN is high, the output OL of the IC 13 becomes high, whereasthe signal UN is low, the output LO of the IC 13 becomes low. Also,similar to the above case, when the signal VP is high, the output HO ofthe IC 240 become high, whereas when the signal VP is low, the output HOof the IC 240 becomes low. Similarly, when the signal VN is high, theoutput LO of the IC 240 becomes high, whereas the signal VN is low, theoutput LO of this IC 240 becomes low. Similar to the above case, whenthe signal WP is high, the output HO of the IC 241 becomes high, whereasthe signal WP is low, the output HO of the IC 241 become low. Also,similar to the above case, when the signal WN is high, the output LO ofthe IC 241 becomes high, whereas when the signal WN is low, the outputLO of the IC 241 becomes low.

As a consequence, for example, in the case that the output HO of the IC13 is high and the output LO of the IC 13 is low; the output HO of theIC 240 is low and the output LO of the IC 240 is high; and the output HOof the IC 241 is low and the output LO of to IC 241 is high, a currentderived from the power supply 201 will flow through the switch 209, theloads 206 and 207, and the switch 212. Also, this current will flowthough the switch 209, the loads 206 and 208, and the switch 214.

It should be understood that both the IC 240 and the IC 241 own the samefunction as the IC 13. In other words, internal circuits of the IC 240and the IC 241 are represented in a similar manner to FIG. 26. Asindicated in FIG. 9, a voltage Vrev1 is produced and a current Irev1flows; a voltage Vrev2 is produced and a current Irev2 flows; and avoltage Vrev3 is produced and a current Irev3 flows. Subsequently, adescription will now be made of such a case that when the voltage Vrev1is produced, the current Irev1 flows. Since operations as to theabove-described current Irev2 and Irev3 are similar to the aboveoperation, explanations thereof are omitted.

FIG. 10 indicates a power converting apparatus according to a seventhembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numeral 250 indicates a core (common mode transformer) made ofa material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 250 by 1 time,the core 250 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current to drive the switches 210, 212, and 214 penetrates the core250 by 1 time along different directions to each other. The magneticfluxes produced within the core 250 are canceled with each other, sothat the core 250 does not function as an inductance component. In otherwords, the delay in the drive speeds of the switches 210, 212, and 214caused by connecting the above-explained core 250 is not produced, butalso the erroneous operation of the IC 13 and also the electricdestruction thereof can be prevented.

Originally, since the above-described current Irev1 flows through the IC13, and the current value is low, a low-cost core can be used as thecore 250.

Also, although the power converting apparatus shown in FIG. 10 arrangedin such a manner that the current Irev1 penetrates the core 250 by 1time. Alternatively, in general, it may be arranged such that theabove-described current Irev1 may penetrate the core 250 by pluraltimes.

Alternatively, although it is arranged by only one core in FIG. 10, itis apparently possible to arrange the power converting apparatus byemploying a plurality of cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 8

FIG. 11 indicates a power converting apparatus according to an eighthembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numeral 251 indicates a core (common mode transformer) made ofa material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 251 by 1 time,the core 251 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 isincreased,this current Irev1 can be suppressed. As a result, it ispossible to prevent the IC 13 from the erroneous operation and theelectric destruction.

A current to drive the switches 209, 211, and 213 penetrates the core251 by 1 time along different directions to each other. The magneticfluxes produced within the core 251 are canceled with each other, sothat the core 251 does not function as an inductance component. In otherwords, the delay in the drive speeds of the switches 209, 211, and 213caused by connecting the above-explained core 251 is not produced, butalso the erroneous operation of the IC 13 and also the electricdestruction thereof can be prevented.

Originally, since the above-described current Irev1 flows through the IC13, and the current value is low, a low-cost core can be used as thecore 251.

Also, the power converting apparatus shown in FIG. 11 is arranged insuch a manner that the current Irev1 penetrates the core 251 by 1 time.Alternatively, in general, it may be arranged such that theabove-described current Irev1 may penetrate the core 251 by pluraltimes.

Alternatively, although it is arranged by only one core in FIG. 11, itis apparently possible to arrange the power converting apparatus byemploying a plurality of cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 9

FIG. 12 indicates a power converting apparatus according to a ninthembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numerals 252 and 253 indicate cores (common mode transformers)made of a material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 252 by 1 timeand the core 253 by 1 time, the cores 251 and 252 may function asinductance components with respect to the current Irev1. In other words,the impedance of the signal path of the above-explained Irev1 isincreased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current used to drive the switches 210, 212, and 214 penetrates thecore 253 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 253 are canceled with eachother, so that the core 253 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches210, 212, and 214 caused by connecting the above-explained core 253 isnot produced, but also the erroneous operation of the IC 13 and also theelectric destruction thereof can be prevented.

Also, a current used to drive the switches 209, 211, and 213 penetratesthe core 252 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 252 are canceled with eachother, so that the core 252 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches209, 211, and 213 caused by connecting the above-explained core 252 isnot produced, but also the erroneous operation of the IC 13 and also theelectric destruction thereof can be prevented.

Originally, since the above-described current Irev1 flows through the IC13, and the current value is low, a low-cost core can be used as thecores 252 and 253.

It should be noted that although the power converting apparatus of FIG.12 is arranged in such a manner that the current Irev1 penetrates thecore 252 and the core 253 by 1 time respectively, generally speaking, itmay be so arranged that the above-described current Irev1 may passthrough the cores 252 and 253 plural times.

Alternatively, it is apparently possible to arrange the power convertingapparatus by employing a plurality of the above-described cores 252 and253, although the power converting apparatus of FIG. 12 is arranged byone core, respectively.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 10

FIG. 13 indicates a power converting apparatus according to a tenthembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numeral 254 indicates a core (common mode transformer) made ofa material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 254 by 2 times,the core 254 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 13 from the erroneous operation and the electricdestruction.

A current used to drive the switches 209 to 214 penetrates the core 254by 1 time along different directions to each other. The magnetic fluxesproduced within the core 254 are canceled with each other, so that thecore 254 does not function as an inductance component. In other words,the delay in the drive speeds of the switches 209 to 214 caused byconnecting the above-explained core 254 is not produced, but also theerroneous operation of the IC 13 and also the electric destructionthereof can be prevented.

Originally, since the above-described current Irev1 flows through the IC13, and the current value is low, a low-cost core can be used as thecore 254.

It should be noted that it may be so arranged that the above-describedcurrent Irev1 may pass through the core 254 more plural times.

Alternatively, it is apparently possible to arrange the power convertingapparatus by employing a plurality of cores 254.

Also, under such a condition that only one core is used due to low costand also, as represented in FIG. 2, the same drive wiring line cannotpenetrate such a single core by more than 2 times because of thearrangement of the power converting apparatus, only such an impedance ofa single core is merely obtained with respect to the current Irev in theembodiments 7 to 9. To the contrary, according to this embodiment, sincethe impedance for two sets of cores can be obtained, the currents Irev1to Irev3 can be furthermore suppressed.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 11

FIG. 14 indicates a power converting apparatus according to an eleventhembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numerals 260 to 262 indicate resistors, and reference numerals263 to 265 show diodes.

In the power converting apparatus with the above-described circuitarrangement, since the resistor 206 is present in the signal paththrough which the current Irev1 flows, this current Irev1 can besuppressed. As a result, it is possible to prevent the IC 13 from theerroneous operation and the electric destruction.

Also, since an impedance component is not newly added to a current pathused to drive the switches 209, 211, and 213 under ON states, there isno delay in the drive speeds of the switches 209, 211, and 213. It is,of course, no problem in such a case that the switches 209, 211, and 213are driven to the OFF states.

Also, since the above-described diode 263 is connected via the powersupply 3 to the VB-terminal of the IC 13 and the VS-terminal thereof,such a diode having a low rating voltage may be used, so that a low-costdiode may be employed as the diode 263. Also, since the diode 264 isconnected via the power supply 230 to the VB-terminal of the IC 240 andthe VS-terminal thereof, and also the diode 265 is connected via thepower supply 232 to the VB-terminal of the IC 241 and the VS-terminalthereof, such diodes having low rating voltage may be used, so thatlow-cost diodes may be employed as these diodes 264 and 265.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 12

In the case that the above-described DC power supplies 3, 230, and 232are, for instance, such DC power supplies containing high frequencynoise and high frequency ripples such as a switching power supply, thereare some possibilities that decoupling capacitors having a smallcapacitance and a better high frequency characteristic are connectedbetween the VB-terminals and the VS-terminals, corresponding to thepower supply voltage terminals of the IC 13, the IC 240, and the IC 241in order not apply the noise and the ripple component. In this case, thecurrent Irev1, the current Irev2, and the current Irev3 will flowthrough the above-described decoupling capacitors, so that the IC 13,the IC 240, and the IC 241 are erroneously operated, and is electricallydestroyed.

FIG. 15 indicates a power converting apparatus according to a twelfthembodiment of the present invention. In this drawing, reference numerals3, 4, 13, 201, 206 to 226, 230 to 233, 240, and 241 indicate the samecircuit elements of FIG. 8, and explanations thereof are omitted.Reference numerals 270 to 272 indicate diodes, reference numerals 273 to275 show capacitors functioning as decoupling capacitors, and referencenumerals 276 to 278 are resistors.

The above-described current Irev1 is blocked by the diode 270, and thereis no path through which the current passes via the DC power supply 3.As a consequence, the current Irev1 will flow via the capacitor 273.However, since the resistor 277 is present, the current Irev1 issuppressed, so that the erroneous operation of the IC 13 and theelectric destruction thereof can be avoided. Also, if the resistancevalue of the resistor 276 may be set to a small value, then theimpedance of the high frequency component with respect to the DC powersupply 3 is not so increased. As a consequence, the high frequency noiseand the high frequency ripple in the DC power supply 3 can be absorbedin the path of the capacitor 273 and the resistor 276.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 13

FIG. 16 represents such a case that a 3-phase power converting circuitis driven by a single IC. In this drawing, reference numerals 201, and206 to 226 indicate the same circuit elements of FIG. 8, andexplanations thereof are omitted. Reference numerals 300 to 303 show DCpower supplies; reference numeral 304 indicates an IC for driving theabove-explained switches 209 and 214; and reference numeral 305 denotesa resistor for detecting a current ILL flowing thorough a 3-phase powerconverting circuit constructed of the above-described switches 209 to214 and diodes 215 to 220.

The above-described DC power supply 300 is a power supply for supplyingelectric power between a VB1-terminal and a VS1-terminal, equal to powersupply voltage supplying terminals of the IC 304 for driving the switch209, and the above-described DC power supply 301 is a power supply forsupplying electric power between a VB2-terminal and a VS2-terminal,equal to power supply voltage supplying terminals of the IC 304 fordriving the switch 211. The above-described DC power supply 302 is apower supply for supplying electric power between a VB3-terminal and aVS3-terminal, equal to power supply voltage supplying terminals of theIC 304 for driving the switch 213, and the above-described DC powersupply 303 is a power supply for supplying electric power between aVCC-terminal and a COM-terminal, equal to power supply voltage supplyingterminals of the IC 304 for driving the switches 210, 212, and 214.

In the above-described IC 304, a signal HIN1 corresponding to the switch209 is entered, another signal LIN1 corresponding to the switch 210 isentered, another signal HIN2 corresponding to the switch 211 is entered,another signal LIN2 corresponding to the switch 212 is entered, anothersignal HIN3 corresponding to the switch 213 is entered, another signalLIN3 corresponding to the switch 214 is entered. When the signal HIN1 ishigh, the output HO1 of the IC 304 becomes high, whereas the signal HIN1is low, the output HO1 of this IC 304 becomes low. Similar to the abovecase, when the signal LIN1 is high, the output LO1 of the IC 304 becomeshigh, whereas the signal LIN1 is low, the output LO1 of the IC 304becomes low. Also, similar to the above case, when the signal HIN2 ishigh, the output HO2 of the IC 304 become high, whereas when the signalHIN2 is low, the output HO2 of the IC 304 becomes low. Similarly, whenthe signal LIN2 is high, the output LO2 of the IC 304 becomes high,whereas the signal LIN2 is low, the output LO2 of this IC 304 becomeslow. Similar to the above case, when the signal HIN3 is high, the outputHO3 of the IC 304 becomes high, whereas the signal HIN3 is low, theoutput HO3 of the IC 304 become low. Also, similar to the above case,when the signal LIN3 is high, the output LO3 of the IC 304 becomes high,whereas when the signal LIN3 is low, the output LO3 of the IC 304becomes low.

The IC 304 detects a voltage of the resistor 305 produced by a currentflowing though the above-described 3-phase power converting circuit.When this detected voltage is higher than a preselected level, the IC304 judges that an excessive current has flown through this 3-phasepower converting circuit, and then forcibly turns OFF theabove-described switches 209 to 214.

The IC 304 owns three sets of the same functions as the IC 13. That isto say, an internal circuit for 1 set of the function is represented ina similar manner to that of FIG. 26. A mechanism is similar to that ofFIG. 26, in which as indicated in FIG. 27, a voltage Vrev1 is producedand a current Irev1 flows, a voltage Vrev2 is produced and a currentIrev2 flows, and a voltage Vrev3 is produced and a current Irev3 flows.Subsequently, a description will now be made of such a case that whenthe voltage Vrev1 is produced, the current Irev1 flows. Since operationsas to the above-described current Irev2 and Irev3 are similar to theabove operation, explanations thereof are omitted.

FIG. 18 indicates a power converting apparatus according to a thirteenthembodiment of the present invention. In this drawing, reference numerals201, 206 to 226, and 300 to 305 indicate the same circuit elements ofFIG. 16, and explanations thereof are omitted. Reference numerals 311 to313 indicate resistors, and reference numerals 314 to 316 representdiodes.

In the power converting apparatus with the above-described circuitarrangement, since the resistor 110 is present in the path through whichthe current Irev1 flows, this current Irev1 can be suppressed. As aresult, it is possible to prevent the IC 13 from the erroneous operationand the electric destruction.

Also, since an impedance component is not newly added to a current pathused to drive the switches 209, 211, and 213 under ON states, there isno delay in the drive speeds of the switches 209, 211, and 213. It is,of course, no problem in such a case that the switches 209, 211, and 213are driven to the OFF states.

Also, since the above-described diode 314 is connected via the powersupply 300 to the VB1-terminal of the IC 304 and the VS1-terminalthereof, such a diode having a low rating voltage may be used, so that alow-cost diode may be employed as the diode 314. Also, since the diode315 is connected via the power supply 301 to the VB2-terminal of the IC304 and the VS2-terminal thereof, and also the diode 316 is connectedvia the power supply 302 to the VB3-terminal of the IC 304 and theVS3-terminal thereof, such diodes having low rating voltage may be used,so that low-cost diodes may be employed as these diodes 315 and 316.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 13--resistor 221--switch209--terminal VS of IC 13) via the resistor 221 is connected under twistline condition for suppressing induction noise. Also, similarly, thedrive signal path (namely, terminal HO of IC 240--resistor 222--switch211--terminal VS of IC 240) via the resistor 222 may be connected undertwist line condition for suppressing induction noise. Also, similarly,the drive path (terminal HO of IC 241--resistor 223--switch213--terminal VS of IC 241) via the resistor 223 may be connected undertwist line condition for suppressing induction noise.

EMBODIMENT 14

In the case that the above-described DC power supplies 300 to 202 are,for instance, such DC power supplies containing high frequency noise andhigh frequency ripples such as a switching power supply, there are somepossibilities that decoupling capacitors having a small capacitance anda better high frequency characteristic are connected between theVB1-terminal and the VS1-terminal between the terminals VB2 and VS2, andbetween the terminals VB3 and VS3, corresponding to the power supplyvoltage terminals of the IC 304 in order not apply the noise and theripple component. In this case, the current Irev1 will flow through theabove-described decoupling capacitors, so that the IC 304 is erroneouslyoperated, and is electrically destroyed.

FIG. 19 indicates a power converting apparatus according to a fifteenthembodiment of the present invention. In this drawing, reference numerals201, 206 to 226, and 300 to 305 indicate the same circuit elements ofFIG. 16, and explanations thereof are omitted. Reference numerals 317 to319 indicate diodes, reference numerals 320 to 322 show capacitorsfunctioning as decoupling capacitors, and reference numerals 323 to 325are resistors.

The above-described current Irev1 is blocked by the diode 317, and thereis no path through which the current passes via the DC power supply 300.As a consequence, the current Irev1 will flow via the capacitor 320.However, since the resistor 323 is present, the current Irev1 issuppressed, so that the erroneous operation of the IC 304 and theelectric destruction thereof can be avoided. Also, if the resistancevalue of the resistor 323 may be set to a small value, then theimpedance of the high frequency component with respect to the DC powersupply 300 is not so increased. As a consequence, the high frequencynoise and the high frequency ripple in the DC power supply 300 can beabsorbed in the path of the capacitor 320 and the resistor 323.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO of IC 304--resistor 221--switch209--terminal VS of IC 304) via the resistor 221 is connected undertwist line condition for suppressing induction noise. Also, similarly,the drive signal path (namely, terminal HO2 of IC 304--resistor222--switch 211--terminal VS2 of IC 304) via the resistor 222 may beconnected under twist line condition for suppressing induction noise.Also, similarly, the drive signal path (namely, terminal HO2 of IC304--resistor 222--switch 211--terminal VS2 of IC 304) via the resistor222 may be connected under twist line condition for suppressinginduction noise. Also, similarly, the drive path (terminal HO3 of IC304--resistor 223--switch 213 terminal VS3 of IC 304 via the resistor223 may be connected under twist line condition for suppressinginduction noise.

EMBODIMENT 15

FIG. 20 indicates a power converting apparatus according to a sixteenthembodiment of the present invention. In this drawing, reference numerals201, 206 to 226, and 300 to 305 indicate the same circuit elements ofFIG. 16, and explanations thereof are omitted. Reference numeral 307indicates a core (common mode transformer) made of a material of, forexample, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 307 by 1 time,the core 307 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 304 from the erroneous operation and the electricdestruction.

A current to drive the switches 210, 212, and 214 penetrates the core307 by 1 time along different directions to each other. The magneticfluxes produced within the core 307 are canceled with each other, sothat the core 307 does not function as an inductance component. In otherwords, the delay in the drive speeds of the switches 210, 212, and 214caused by connecting the above-explained core 307 is not produced, butalso the erroneous operation of the IC 304 and also the electricdestruction thereof can be prevented.

Also, since the above-described ILL penetrates the core 307 by 1 timealong different directions to each other, and then the magnetic fluxesproduced within the core 307 are canceled with each other, theabove-described core 307 does not function as an inductance component.In other words, no adverse influence is given to the above-describedILL, which is caused by connecting the core 307.

Originally, since the above-described current Irev1 flows through the IC304, and the current value is low, a low-cost core can be used as thecore 307. Moreover, the magnetic fluxes produced by the current ILLwithin the core 307 are canceled with each other, such a low-cost coremay be used.

Also, the power converting apparatus shown in FIG. 21 is arranged insuch a manner that the current Irev1 penetrates the core 307 by 1 time.Alternatively, in general, it may be arranged such that theabove-described current Irev1 may penetrate the core 307 by pluraltimes.

Alternatively, although it is arranged by only one core in FIG. 21, itis apparently possible to arrange the power converting apparatus byemploying a plurality of cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO1 of IC 304--resistor 221--switch209--terminal VS1 of IC 304) via the resistor 221 is connected undertwist line condition for suppressing induction noise. Also, similarly,the drive signal path (namely, terminal HO2 of IC 304--resistor222--switch 211--terminal VS2 of IC 304) via the resistor 222 may beconnected under twist line condition for suppressing induction noise.Also, similarly, the drive path (terminal HO3 of IC 304 resistor223--switch 213--terminal VS3 of IC 304) via the resistor 223 may beconnected under twist line condition for suppressing induction noise.

EMBODIMENT 16

FIG. 21 indicates a power converting apparatus according to a sixteenthembodiment of the present invention. In this drawing, reference numerals201, 206 to 226, and 300 to 305 indicate the same circuit elements ofFIG. 16, and explanations thereof are omitted. Reference numeral 306indicates a core (common mode transformer) made of a material of, forexample, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 306 by 1 time,the core 306 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 304 from the erroneous operation and the electricdestruction.

A current to drive the switches 209, 211, and 213 penetrates the core306 by 1 time along different directions to each other. The magneticfluxes produced within the core 251 are canceled with each other, sothat the core 306 does not function as an inductance component. In otherwords, the delay in the drive speeds of the switches 209, 211, and 213caused by connecting the above-explained core 306 is not produced, butalso the erroneous operation of the IC 304 and also the electricdestruction thereof can be prevented.

Also, since the current ILL does not penetrate the core 306, there is noadverse influence given to the current flowing thorough theabove-explained 3-phase power converting circuit. Furthermore, generallyspeaking, when the current ILL is a large current, the main circuitwiring line used to cause the above-described current ILL to passtherethrough is made wide. However, according to this embodiment, sincethe main circuit wiring line need not be connected to the core 306, thearrangement can be made easy.

Originally, since the above-described current Irev1 flows through the IC304, and the current value is low, a low-cost core can be used as thecore 306.

Also, the power converting apparatus shown in FIG. 18 is arranged insuch a manner that the current Irev1 penetrates the core 306 by 1 time.Alternatively, in general, it may be arranged such that theabove-described current Irev1 may penetrate the core 306 by pluraltimes.

Alternatively, although it is arranged by only one core in FIG. 18, itis apparently possible to arrange the power converting apparatus byemploying a plurality of cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO1 of IC 304--resistor 221--switch209--terminal VS1 of IC 304) via the resistor 221 is connected undertwist line condition for suppressing induction noise. Also, similarly,the drive signal path (namely, terminal HO2 of IC 304--resistor222--switch 211--terminal VS2 of IC 304) via the resistor 222 may beconnected under twist line condition for suppressing induction noise.Also, similarly, the drive path (terminal HO3 of IC 304--resistor223--switch 213--terminal VS3 of IC 304) via the resistor 223 may beconnected under twist line condition for suppressing induction noise.

EMBODIMENT 17

FIG. 22 indicates a power converting apparatus according to aseventeenth embodiment of the present invention. In this drawing,reference numerals 201, 206 to 226, and 300 to 305 indicate the samecircuit elements of FIG. 16, and explanations thereof are omitted.Reference numerals 308 and 309 indicate cores (common mode transformers)made of a material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 308 by 1 timeand the core 309 by 1 time, the cores 308 and 309 may function asinductance components with respect to the current Irev1. In other words,the impedance of the signal path of the above-explained Irev1 isincreased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 304 from the erroneous operation and the electricdestruction.

A current used to drive the switches 209, 211, and 213 penetrates thecore 308 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 308 are canceled with eachother, so that the core 308 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches209, 211, and 213 caused by connecting the above-explained core 308 isnot produced, but also the erroneous operation of the IC 304 and alsothe electric destruction thereof can be prevented.

Also, a current used to drive the switches 210, 212, and 214 penetratesthe core 309 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 309 are canceled with eachother, so that the core 309 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches210, 212, and 214 caused by connecting the above-explained core 309 isnot produced, but also the erroneous operation of the IC 304 and alsothe electric destruction thereof can be prevented.

Also, the above-described current ILL penetrates the core 309 by 1 timealong different directions to each other, and the magnetic fluxesproduced within the core 309 are canceled with each other, so that thecore 309 does not function as an inductance component. In other words,there is no adverse influence caused by connecting the core 309 withrespect to the above-described current ILL.

Originally, since the above-described current Irev1 flows through the IC304, and the current value is low, a low-cost core can be used as thecore 308. Furthermore, since the magnetic fluxes produced by theabove-explained current ILL within the core 309, a low-cost core canalso be used as the core 309.

It should be understood that the power converting apparatus of FIG. 22is so arranged by that the current Irev1 penetrates the core 308 and thecore 309 by 1 time. Alternatively, in general, it may be arranged suchthat the above-described current Irev1 may penetrate the cores 308 and309 plural times.

Furthermore, although the power converting apparatus is arranged byemploying only one core, respectively, in FIG. 22, it may be arranged byusing a plurality of the above-explained cores.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO1 of IC 304--resistor 221--switch209--terminal VS1 of IC 304) via the resistor 221 is connected undertwist line condition for suppressing induction noise. Also, similarly,the drive signal path (namely, terminal HO2 of IC 304--resistor222--switch 211--terminal VS2 of IC 304) via the resistor 222 may beconnected under twist line condition for suppressing induction noise.Also, similarly, the drive path (terminal HO3 of IC 304--resistor223--switch 213--terminal VS3 of IC 304) via the resistor 223 may beconnected under twist line condition for suppressing induction noise.

EMBODIMENT 18

FIG. 23 indicates a power converting apparatus according to aneighteenth embodiment of the present invention. In this drawing,reference numerals 201, 206 to 226, and 300 to 305 indicate the samecircuit elements of FIG. 16, and explanations thereof are omitted.Reference numeral 310 indicates a core (common mode transformer) made ofa material of, for example, ferrite and the like.

In the power converting apparatus with the above-described circuitarrangement, since the current Irev1 penetrates the core 310 by 2 times,the core 310 may function as an inductance component with respect to thecurrent Irev1. In other words, the impedance of the signal path of theabove-explained Irev1 is increased.

When the impedance of the signal path of the current Irev1 is increased,this current Irev1 can be suppressed. As a result, it is possible toprevent the IC 304 from the erroneous operation and the electricdestruction.

A current used to drive the switches 209, 211, and 213 penetrates thecore 310 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 310 are canceled with eachother, so that the core 310 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches209, 211, and 213 caused by connecting the above-explained core 310 isnot produced, but also the erroneous operation of the IC 304 and alsothe electric destruction thereof can be prevented.

Also, a current used to drive the switches 210, 212, and 214 penetratesthe core 310 by 1 time along different directions to each other. Themagnetic fluxes produced within the core 310 are canceled with eachother, so that the core 310 does not function as an inductancecomponent. In other words, the delay in the drive speeds of the switches210, 212, and 214 caused by connecting the above-explained core 310 isnot produced, but also the erroneous operation of the IC 304 and alsothe electric destruction thereof can be prevented.

Also, the above-described current ILL penetrates the core 310 by 1 timealong different directions to each other, and the magnetic fluxesproduced within the core 310 are canceled with each other, so that thecore 310 does not function as an inductance component. In other words,there is no adverse influence caused by connecting the core 310 withrespect to the above-described current ILL.

Originally, since the above-described current Irev1 flows through the IC304, and the current value is low, a low-cost core can be used as thecore 105. Furthermore, since the magnetic fluxes produced by theabove-explained current ILL within the core 310, a low-cost core canalso be used as the core 310.

It should be understood that the power converting apparatus of FIG. 23is so arranged by that the current Irev1 penetrates the core 310 by 2times. Alternatively, in general, it may be arranged such that theabove-described current Irev1 may penetrate the core 310 plural times.

Furthermore, although the power converting apparatus is arranged byemploying only one core, respectively, in FIG. 23, it may be arranged byusing a plurality of the above-explained cores.

Also, under such a condition that only one core is used due to low costand also, as represented in FIG. 2, the same drive wiring line cannotpenetrate such a single core by more than 2 times because of thearrangement of the power converting apparatus, only such an impedance ofa single core is merely obtained with respect to the current Irev in theembodiments 7 to 9. To the contrary, according to this embodiment, sincethe impedance for two sets of cores can be obtained, the currents Irev1to Irev3 can be furthermore suppressed.

Also, in the drawing, apparently it may be arranged that the drivesignal path (namely, terminal HO1 of IC 304--resistor 221--switch209--terminal VS1 of IC 304) via the resistor 221 is connected undertwist line condition for suppressing induction noise. Also, similarly,the drive signal path (namely, terminal HO2 of IC 304--resistor222--switch 211--terminal VS2 of IC 304) via the resistor 222 may beconnected under twist line condition for suppressing induction noise.Also, similarly, the drive path (terminal HO3 of IC 304 resistor223--switch 213--terminal VS3 of IC 304) via the resistor 223 may beconnected under twist line condition for suppressing induction noise.

As previously described, the present invention may achieve thebelow-mentioned effects.

The power converting apparatus, according to the present invention, iscomprised of: an electric valve group containing a first electric valveand a second electric valve, which have first terminals, secondterminals, and third terminals, and in which the first terminals and thethird terminals are opened/closed by supplying an electric signalbetween the second terminals and the third terminals, and also the firstelectric valve is series-connected to the second electric valve; a powersupply group containing a first power supply and a second power supplyseries-connected to the first power supply, the power supply group beingconnected in parallel to the electric valve group; a load connectedbetween a junction point defined by the first electric valve and thesecond electric valve, and another junction point defined by the firstpower supply and the second power supply; control means connected to thesecond terminals in the first and second electric valves and also to thethird terminals in the first and second electric valves, foropening/closing the first and second electric valves in a complementarymanner; a third power supply, one end of which is connected to thecontrol means, and the other end of which is connected to the thirdterminal in the first electric valve; a fourth power supply, one end ofwhich is connected to the control means, and the other end of which isconnected to the third terminal in the second valve; and impedanceincreasing means for increasing an impedance of a signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the electricvalve. As a result, it is possible to suppress the current flowingthrough the signal path defined from the third terminal in the secondelectric valve via the control means and the third power supply to thethird terminal in the first electric valve, and also it is possible toprevent the control means from the erroneous operation and the electricdestruction.

Also, since the impedance increasing means is the transformer, thisimpedance increasing means can be easily constructed.

Furthermore, the transformer is hollow; and a line used to connect thesecond terminal in the second electric valve with the control means andanother line used to connect the third terminal in the second electricvalve with the control means are provided in such a manner that both thelines penetrate the hollow of the transformer. As a consequence, it ispossible to suppress the current flowing through the signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the firstelectric valve, and also the erroneous operation and the electricdestruction of the control means can be avoided.

Furthermore, the transformer is hollow; and a line used to connect thesecond terminal in the first electric valve with the control means andanother line used to connect the third terminal in the first electricvalve with the control means are provided in such a manner that both thelines penetrate the hollow of the transformer. As a consequence, it ispossible to suppress the current flowing through the signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the firstelectric valve, and also the erroneous operation and the electricdestruction of the control means can be avoided.

Also, the line used to connect the second terminal in the secondelectric valve with the control means and the line used to connect thethird terminal in the second electric valve with the control means areprovided in such a manner that both the lines penetrate the hollow ofthe transformer plural times. As a consequence, it is possible tofurther suppress the current flowing through the signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the firstelectric valve.

Moreover, the line used to connect the second terminal in the firstelectric valve with the control means and the line used to connect thethird terminal in the first electric valve with the control means areprovided in such a manner that both the lines penetrate the hollow ofthe transformer plural times. As a consequence, it is possible tofurther suppress the current flowing through the signal path definedfrom the third terminal in the second electric valve via the controlmeans and the third power supply to the third terminal in the firstelectric valve.

Furthermore, the transformer is hollow; and a line used to connect thesecond terminal in the first electric valve with the control means,another line used to connect the third terminal in the first electricvalve with the control means, another line used to connect the secondterminal in the second electric valve with the control means, andanother line used to connect the third terminal in the second electricvalve with the control means are provided in such a manner that thelines penetrate the hollow of the transformer. As a consequence, it ispossible to further suppress the current flowing through the signal pathdefined from the third terminal in the second electric valve via thecontrol means and the third power supply to the third terminal in thefirst electric valve.

Also, since the impedance increasing means is the resistor, thisimpedance increasing means can be simply provided within a small space.

Moreover, since the third power supply is connected via the resistor tothe control means, this resistor can suppress the current flowingthrough the signal path defined from the third terminal in the secondelectric valve via the control means and the third power supply to thethird terminal in the first electric valve.

Also, since the power converting apparatus is comprised of a diodeconnected in parallel to the resistor, the current from the third powersupply to the control means can be properly supplied via the diode.

Also, the impedance increasing means includes: a diode series-connectedbetween the control means and the third power supply; a capacitorconnected in parallel to the diode and the third power supply; and aresistor series-connected to the capacitor and also connected inparallel to both the diode and the third power supply. As a consequence,it is possible to suppress the current flowing through the signal pathdefined from the third terminal in the second electric valve via thecontrol means and the third power supply to the third terminal in thefirst electric valve.

The power converting apparatus, according to the present invention, iscomprised of: a first electric valve provided so as to supply power froma first power supply to a load; a second electric valve provided so asto supply power from a second power supply to the load; control meansfor controlling a switching operation of conducting the first electricvalve and the second electric valve in a complementary manner bysupplying a switching control signal to a control electrode of the firstelectric valve and also to a control electrode of the second electricvalve; a third power supply connected between one of main electrodes ofthe first electric valve and the control means; a fourth power supplyconnected between one of main electrodes of the second electric valveand the control means; and impedance increasing means provided in aseries circuit constituted by a main electrode of the second electricvalve, the control means, the third power supply, and a main electrodeof the first electric valve, for increasing an impedance of the seriescircuit. As a consequence, it is possible to suppress the currentflowing through the series circuit, and also, the erroneous operationand the malfunction of the control means can be prevented.

INDUSTRIAL UTILIZATION

As previously described, the power converting apparatus according to thepresent invention is suitably used as the power switching element andthe power converting apparatus for driving this power switching element.

What is claimed is:
 1. A power converting apparatus comprising:anelectric valve group containing a first electric valve and a secondelectric valve, which have first terminals, second terminals, and thirdterminals, and in which said first terminals and said third terminalsare opened/closed by supplying an electric signal between said secondterminals and said third terminals, and also said first electric valveis series-connected to said second electric valve; a power supply groupcontaining a first power supply and a second power supplyseries-connected to said first power supply, said power supplyseries-connected to said first power supply, said power supply groupbeing connected in parallel to said electric valve group; a loadconnected between a junction point defined by the connection of saidfirst electric valve and said second electric valve, and anotherjunction point defined by the connection of said first power supply andsaid second power supply; control means connected to the secondterminals of said first and second electric valves and also to the thirdterminals of said first and second electric valves, for opening/closingsaid first and second electric valves in a complementary manner; a thirdpower supply, one end of which is connected to said control means, andthe other end of which is connected to the third terminal in said firstelectric valve; a fourth power supply, one end of which is connected tosaid control means, and the other end of which is connected to saidthird terminal in said second valve; and impedance increasing means forincreasing an impedance of a signal path defined from the third terminalin said second electric valve via said control means and said thirdpower supply to the third terminal in said electric valve.
 2. A powerconverting apparatus as claimed in claim 1 wherein:said impedanceincreasing means is a transformer.
 3. A power converting apparatus asclaimed in claim 2 wherein:said transformer is hollow; and a line usedto connect said second terminal in said second electric valve with saidcontrol means and another line used to connect said third terminal insaid second electric valve with said control means are provided in sucha manner that both said lines penetrate the hollow of said transformer.4. A power converting apparatus as claimed in claim 2 wherein:saidtransformer is hollow; and a line used to connect said second terminalin said first electric valve with said control means and another lineused to connect said third terminal in said first electric valve withsaid control means are provided in such a manner that both said linespenetrate the hollow of said transformer.
 5. A power convertingapparatus as claimed in claim 3 wherein:the line used to connect saidsecond terminal in said second electric valve with said control meansand the line used to connect said third terminal in said second electricvalve with said control means are provided in such a manner that bothsaid lines penetrate the hollow of said transformer plural times.
 6. Apower converting apparatus as claimed in claim 4 wherein:the line usedto connect said second terminal in said first electric valve with saidcontrol means and the line used to connect said third terminal in saidfirst electric valve with said control means are provided in such amanner that both said lines penetrate the hollow of said transformerplural times.
 7. A power converting apparatus as claimed in claim 2wherein:said transformer is hollow; and a line used to connect thesecond terminal in said first electric valve with said control means,another line used to connect the third terminal in said first electricvalve with said control means, another line used to connect the secondterminal in said second electric valve with said control means, andanother line used to connect the third terminal in said second electricvalve with said control means are provided in such a manner that saidlines penetrate the hollow of said transformer.
 8. A power convertingapparatus as claimed in claim 1 wherein:said impedance increasing meansis a resistor.
 9. A power converting apparatus as claimed in claim 8wherein:said third power supply is connected via said resistor to saidcontrol means.
 10. A power converting apparatus as claimed in claim 9further comprising:a diode connected in parallel to said resistor.
 11. Apower converting apparatus as claimed in claim 1 wherein:said impedanceincreasing means includes:a diode series-connected between said controlmeans and said third power supply; a capacitor connected in parallel tothe series connection of said diode and said third power supply; and aresistor series-connected to said capacitor and also connected inparallel to the series connection of said diode and said third powersupply.
 12. A power converting apparatus comprising:a first electricvalve provided so as to supply power from a first power supply to aload; a second electric valve provided so as to supply power from asecond power supply to said load; control means for controlling aswitching operation of said first electric valve and said secondelectric valve in a complementary manner by supplying a switchingcontrol signal to a control electrode of said first electric valve andalso to a control electrode of said second electric valve; a third powersupply connected between one of main electrodes of said first electricvalve and said control means; a fourth power supply connected betweenone of main electrodes of said second electric valve and said controlmeans; and impedance increasing means provided in a series circuitconstituted by a main electrode of said second electric valve, saidcontrol means, said third power supply, and a main electrode of saidfirst electric valve, for increasing an impedance of said seriescircuit.
 13. A power converting apparatus as claimed in claim 12wherein:said first power supply is identical to said second powersupply.